Time Division Multiplexing is a scheme in which a plurality of signals are combined for transmission on a single communications line or channel. Each signal is broken up into a plurality of segments having a short duration. A circuit that combines signals at a source end of a communications link is known as a multiplexer. The multiplexer accepts input signals from a first plurality of end users, breaks each input signal into segments, and assigns the segments to a composite signal in a rotating, repeating sequence. Therefore, the composite signal contains data from each of the first plurality of end users. At a destination end, the composite signal is separated into the input signal segments by a circuit known as a demultiplexer. The separated input signal segments are then routed to a second plurality of end users.
TDM data flows may be transmitted in a native format and time bursted over a first mile Ethernet drop (one or multiple hops) along with regular Ethernet traffic. Time bursting generally involves an intermittent asynchronous transmission of a specific amount of data for a specific amount of time.
Currently, packetization of TDM data flows is required for transmission. However, packetization of TDM data flow is costly per bit. Two current methods involve packetized Time Division Multiplexing over Internet Protocol (TDMoIP) and native TDM on physical layer (PHY) sideband.
For TDMoIP, packetizing TDM data flows requires greater hardware and software invested solutions thereby raising costs to first mile outstations (e.g., customer premise equipments). Further, clocking in TDMoIP requires extensive computing resources, such as multiple steps of packetization, latency and jitter dynamic input/output (i/o) buffering, encapsulation into User Datagram Protocol (UDP), Internet Protocol (IP) and Ethernet, and management overheads of associated tiered address space, for example. Therefore, TDMoIP is not cost effective or efficient for metro networking on Synchronous Optical Network (SONET).
For native TDM on PHY sideband, investments in a modified Ethernet PHY are required to support passthrough TDM sideband, as current PHYs will not support this functionality. Thus, a new PHY upgrade to existing systems is needed.
Computer network traffic generally encompasses traffic from telephone, video as well as other time-sensitive sources. As conventional computer networks are not adequately designed to handle such real-time traffic, collisions and congestion oftentimes lead to delays and other inefficiencies. In Ethernet applications, the use of variable packet sizes and carrier sense multiple access with collision detect (CSMA/CD) for link access and control creates an unpredictable and less controllable environment for assuring quality of service.
Ethernet over Sonet/SDH may use a more traditional means of carrying packets on an add/drop collector where traditional circuit oriented TDM flows may be carried in native format. This concept of adding Ethernet transport into a Sonet/SDH infrastructure comes with adding complexity and higher cost to add/drop devices used for collector network purposes.
In view of the foregoing, it would be desirable to provide a technique for implementing a tunable add/drop collector having at least two bursting ports for supporting dedicated and shared timeslotting which overcomes the above-described inadequacies and shortcomings. More particularly, it would be desirable to provide a technique for implementing a tunable add/drop collector having at least two bursting ports for supporting dedicated and shared timeslotting in an efficient and cost effective manner.